The TCP-1 Ring Complex (TRiC) is an essential, conserved chaperone required for the folding and activation of 10-15% of the proteins encoded by the human genome. Among its substrates are a large number of cell cycle regulators and tumor suppressor proteins. Currently, no specific agonists or antagonists are available for this key regulator of cellular protein folding. Given the early promise of other chaperone-directed inhibitors as cancer therapeutics, we believe that inhibitors of TRiC activity may also selectively target transformed cells. In this project, we plan to: 1) Identify small molecule inhibitors of TRiC with high throughput screening (HTS) using a homogenous time resolved fluorescence (HTRF) assay against the Molecular Libraries Screening Center Network compound collection. 2) Test the inhibitors from HTS for specificity to TRiC and optimize candidate compounds for activation or inhibition of TRiC-mediated actin folding. 3) Characterize the toxicity and bioavailability of molecules that modulate TRiC activity in tissue culture and measure the efficacy of candidates for inhibition of protein folding in vivo. PUBLIC HEALTH RELEVANCE: The chaperonin TRiC/CCT is essential for folding a large array of cellular proteins, including many cell cycle regulators, yet no inhibitors or modulators of its activity are available. Obtaining inhibitors for this chaperonin would be invaluable for understanding its biological function, and could also lead to a novel type of anti-cancer drugs.